Communication
Speak to your partner and apologize face to face. Let them know the reasons for your apology.
Physical Touches
Look into the eyes, hold the hands and hug to apologize.
Letters
Write apology letters to your partner.
Art
Draw pictures and paint. You could do a handmade card to your partner, stating your apology. Use pictures and visual cards to express if needed.
Discuss with your partner and break down complex issues that surface between each other. Work on the easiest problem together before moving on to the challenging ones.
Provide mutual support in preventing the problem from reccurring.
Do not be egoistic when seeking forgiveness. Never use forgiveness as an opportunity to exercise power and control.
Be aware not to cause the same pain again to your partner after asking for forgiveness.
Exchange gifts by buying flowers or cooking favorite dishes. Do not always wait for valentine days, birthdays or new year, to express your love. Love is ever relating and needs daily consistent efforts.
It takes time to heal. Bad times will pass, use uncertain and bitter moments as opportunities to exercise caution and enhance your bond.